Four reasons to not wait until January to enroll in an ACA health plan

Open enrollment for individual/family health coverage begins each November 1 and continues until at least January 15 in nearly every state. (Idaho ends its open enrollment period in December, but Idaho also started early, allowing people to enroll starting in mid-October.)

For several years, open enrollment ended in mid-December. So the fact that enrollment now continues until at least mid-January in nearly every state does give people some extra wiggle room during the busy holiday season. But for most people, December 15 is still the soft deadline to keep in mind. In most states, that’s the last day you can enroll in coverage that will take effect January 1 (some states have a later deadline). And that’s important for several reasons.

1. Currently uninsured? Delaying your enrollment will mean no coverage in January.

If you’re aren't already enrolled in ACA-compliant coverage, the open enrollment period that starts November 1 and end in mid-January (in most states) is your chance to change that for the coming year. But if you wait until after December 15 to enroll, you won’t have coverage in place when the new year begins. Instead, you’ll be waiting until February 1 for your coverage to begin.

2. Currently uninsured or enrolled in a non-Marketplace plan? Delayed enrollment might mean missing out on free money.

If you considered Marketplace coverage in the past and found it to be unaffordable, you might currently be uninsured or enrolled in a plan that isn’t regulated by the ACA. Or you might have opted to buy ACA-compliant coverage outside the exchange, if you weren’t eligible for premium tax credits (subsidies) the last time you looked.

But thanks to the American Rescue Plan and Inflation Reduction Act, many people who weren’t eligible for subsidies before 2021 will find that they are now. (These subsidy enhancements are available through the end of 2025, but additional legislation would be necessary to extend them beyond that.)

In addition to being more widely available, premium subsidies are also larger than they were before the American Rescue Plan. People who didn’t enroll in the past due to the cost may find that coverage now fits in their budget.

Four out of five people shopping for coverage in the 31 states that use the federally run Marketplace (HealthCare.gov) will find that they can get coverage for $10/month or less.¹ And millions of uninsured Americans are eligible for premium-free coverage in the Marketplace, but may not realize this.

Waiting until after December 15 to enroll in coverage during open enrollment will mean that you leave all that money on the table for January, since your coverage – and subsidy – wouldn't take effect until February. You can use our subsidy calculator to get an idea of the size of your subsidy. Then, make sure you enroll by December 15 so that you’re eligible to claim the subsidy for all 12 months of the year.

3. Letting your plan auto-renew? You might be in for a surprise.

If you already had coverage through the Marketplace and are planning to just let it auto-renew for the next year, you learned on the following January 1 that your coverage and premium that aren’t what you expected.

Even if you’re 100% happy with the plan you have now, you owe it to yourself to spend at least a little time checking out the available options before December 15. The premium that your insurer charges may be changing for the coming year. (It likely changed for 2025.) And your subsidy amount might also be changing, especially if there are changes to the list of participating Marketplace insurers in your area. At least 19 states had new or exiting insurers for 2025. (Here's more about how this can potentially change subsidy amounts.)

Your insurer might also be making changes to your benefits, provider network, or covered drug list – or even discontinuing the plan altogether and replacing it with a new one. In short, the plan and price you have on January 1 might be quite different from what you have now.

This is part of the reason HHS opted to extend the open enrollment period starting in 2022, to give people a chance for a “do-over” if their auto-renewed plan isn’t what they expected. In nearly every state, you’ll have until at least January 15 to pick a new plan. But that plan selection won’t be retroactive to January 1 if you enroll in the final few weeks of open enrollment.

4. Out-of-pocket expenses won’t transfer in February or March.

What if you’re enrolled in a Marketplace plan and let it auto-renew for the next plan year, and then decide after December 15 that you’d rather have a different plan? Thanks to the extended open enrollment period in nearly every state, you can do that and your new plan will take effect in February.

But it’s important to understand that you’ll be starting over with a new plan in February. This means the out-of-pocket costs counted against your deductible and out-of-pocket maximum will reset to $0, even if you have out-of-pocket expenses in January.

Out-of-pocket expenses reset to $0 on January 1 for all Marketplace plans, so your auto-renewed policy will start over with a new deductible at that point. But if you need medical care in January (and have associated out-of-pocket costs) before your new plan takes effect in February, you’ll potentially have a higher out-of-pocket exposure for the whole year than you would have if you’d picked your new plan by December 15 and had it start January 1.

All of this is a reminder that while most enrollees have until at least mid-January to sign up for new coverage, it’s in your best interest to get your plan selection sorted out by December 15.

Louise Norris is an individual health insurance broker who has been writing about health insurance and health reform since 2006. She has written dozens of opinions and educational pieces about the Affordable Care Act for healthinsurance.org.